Paper

{
  "raw_xml": "<entry>\n    <id>http://arxiv.org/abs/2602.23563v1</id>\n    <title>Characterization of UV optical components for photon detector calibration in liquid argon TPCs</title>\n    <updated>2026-02-27T00:16:20Z</updated>\n    <link href='https://arxiv.org/abs/2602.23563v1' rel='alternate' type='text/html'/>\n    <link href='https://arxiv.org/pdf/2602.23563v1' rel='related' title='pdf' type='application/pdf'/>\n    <summary>Large liquid argon time projection chambers (LArTPCs) require stable and well-characterized delivery of ultraviolet (UV) light for in situ calibration of photosensors at cryogenic temperatures. This article reports bench-top and cryogenic measurements of the optical components used in a UV light calibration system, including multi-mode fused-silica fibers, SMA-to-SMA connectors, optical fiber feedthroughs, and light-diffuser assemblies. Light loss in several fiber types and SMA connectors was measured across wavelengths from \\qtyrange{275}{970}{nm}. In addition, light-loss measurements of the tested fibers after several liquid-nitrogen thermal cycles showed no statistically significant degradation relative to baseline measurements, and high-rate pulsed exposure (30-90 million pulses from a \\qty{275}{nm} LED) likewise showed no measurable aging in jacketed fibers. A compact, palm-sized, 3D-printed PEEK diffuser housing with stacked UV-grade fused-silica diffusers yields Lambertian emission and the most uniform angular distribution. Optical components exhibiting improved UV transmission were deployed successfully in multiple DUNE small- and large-scale prototypes, demonstrating reliable operation of UV light calibration systems. These findings inform component selection and calibration procedures for achieving reliable, uniform UV light delivery in large-scale cryogenic detectors such as DUNE.</summary>\n    <category scheme='http://arxiv.org/schemas/atom' term='physics.ins-det'/>\n    <category scheme='http://arxiv.org/schemas/atom' term='hep-ex'/>\n    <published>2026-02-27T00:16:20Z</published>\n    <arxiv:comment>31 pages, 28 figures</arxiv:comment>\n    <arxiv:primary_category term='physics.ins-det'/>\n    <author>\n      <name>B. Behera</name>\n    </author>\n    <author>\n      <name>M. Bilal Azam</name>\n    </author>\n    <author>\n      <name>Z. Djurcic</name>\n    </author>\n    <author>\n      <name>A. Heindel</name>\n    </author>\n    <author>\n      <name>I. Helgeson</name>\n    </author>\n    <author>\n      <name>T. Hyden</name>\n    </author>\n    <author>\n      <name>D. Leon Silverio</name>\n    </author>\n    <author>\n      <name>S. Magill</name>\n    </author>\n    <author>\n      <name>D. A. Martinez Caicedo</name>\n    </author>\n    <author>\n      <name>M. Oberling</name>\n    </author>\n    <author>\n      <name>K. Pickner</name>\n    </author>\n    <author>\n      <name>A. Rafique</name>\n    </author>\n    <author>\n      <name>J. Rodríguez Rondon</name>\n    </author>\n    <author>\n      <name>D. Torres Muñoz</name>\n    </author>\n    <author>\n      <name>C. Winkers</name>\n    </author>\n    <author>\n      <name>L. Xia</name>\n    </author>\n  </entry>"
}